As highlighted in the post by the glorious @Brian Blessed April is Ape-ril which is like Movember for apes specifically orangutans.

Now the challenge is to grow a beard or dye it orange well for me growing a beard isn't a challenge and there's already ginger in my beard so I've a new ape inspired challenge. Apes like climbing and swinging about so I'm going to challenge myself to do pull-ups/chin up to raise money for this cause.
How the bloody hell will you do that? I hear you cry!
Simple! I will do a pull up/chin up for every pound that is donated to this JustGiving page.
I encourage others to get involved and take-up this challenge if you can. #pullupperpound #pound4pullups 

A little bit about me for context I'm currently floating around 16.5st 104kg or 231lb so not light. I could be very generous and say its mostly relaxed muscle but it been far too long since a saw a gym for that to be true. Now I used to be able to do quite a few pulls/chin-ups in one go but i was lighter and healthier then (also younger) the last check I could do 2 back to back. So I know this is going to be hard and probably painful but it is for 2 very good causes. With it being Painful I can put peoples sadistic streak to good use.

Some information about S.O.S

Sumatran orangutans are critically endangered, with only around 14,600 left in the wild. Indonesia has the highest rate of forest destruction in the world.

SOS protects orangutans, their forest and their future by:
• supporting local people to improve their income at the same time as protecting the rainforest
• rescuing orangutans and resolving conflicts between villages and orangutans
• campaigning on issues threatening the survival of orangutans in the wild.
• restoring damaged orangutan habitat through tree planting programmes